When athletic shoes should be replaced depends upon amount of usage, signs of wear and age of the shoe. The four main components of an athletic that can break down or wear out: outer sole, midsole, heel counter and shank or cut out area of the shoe.
The outer sole material is made of a carbon rubber, which is meant to be very abrasion resistant. Some athletic shoes will have a harder and more resilient rubber at the heel of the shoe since this is where most of the wear will occur. Once the outersole has worn through to midsole or there is more than 4mm difference from the other side of the heel the shoe should be replaced. Refer to image A.
The mid-sole is normally composed of a foam material: Ethylene Vinyl Acetate (EVA), Polyurethane (PU) or a blend of both materials. The midsole is intended to be shock absorbing and in some shoes serves to control excessive foot motion. After certain amount of repetitive load is placed on the midsole it will compress not rebound and absorb shock or control the foot as well as it did when new. In some cases, the midsole can deform and compress unevenly which can create an alignment change of the foot. This can lead to over use type injuries.
Midsoles should be considered worn out:
- After 300-500 miles of running or walking, 45-60 hours of basketball, aerobic dance or tennis.
- Shows signs of unevenness when placed on flat surface.
- Display noticeable creasing.
Refer to image B and C.
The heel counter of the shoe helps hold the heel on top of the midsole and prevents excessive heel motion. The heel counter should be considered broken down when it feels flexible when compressed side to side, or appears deviate to one side when viewing from the rear of the shoe. Refer to image D and E.
The shank or mid cut area of the shoe can fatigue with use. This area of the shoe should be inspected periodically.
Even without use shoes can “wear out”. Depending upon the environment the shoes are kept in; the outsole, midsole and some of the upper materials can dry out and not function optimally. Therefore, it is best to replace athletic shoes that are over a year old whether they are worn out or not.
Replacing athletic shoes when necessary maybe costly in the short term, but will prevent injuries and keep you active in “the long run”.
Foot problems most often happen when there is nerve damage, also called neuropathy. This can cause tingling, pain (burning or stinging), or weakness in the foot. It can also cause loss of feeling in the foot, so you can injure it and not know it. Poor blood flow or changes in the shape of your feet or toes may also cause problems.
Although it can hurt, diabetic nerve damage can also lessen your ability to feel pain, heat, and cold. Loss of feeling often means you may not feel a foot injury. You could have a tack or stone in your shoe and walk on it all day without knowing. You could get a blister and not feel it. You might not notice a foot injury until the skin breaks down and becomes infected.
Nerve damage can also lead to changes in the shape of your feet and toes. Ask your health care provider about special therapeutic shoes, rather than forcing deformed feet and toes into regular shoes.
Diabetes can cause changes in the skin of your foot. At times your foot may become very dry. The skin may peel and crack. The problem is that the nerves that control the oil and moisture in your foot no longer work.
After bathing, dry your feet and seal in the remaining moisture with a thin coat of plain petroleum jelly, an unscented hand cream, or other such products.
Do not put oils or creams between your toes. The extra moisture can lead to infection. Also, don’t soak your feet — that can dry your skin.
Calluses occur more often and build up faster on the feet of people with diabetes. This is because there are high-pressure areas under the foot. Too much callus may mean that you will need therapeutic shoes and inserts.
Calluses, if not trimmed, get very thick, break down, and turn into ulcers (open sores). Never try to cut calluses or corns yourself – this can lead to ulcers and infection. Let your health care provider cut your calluses. Also, do not try to remove calluses and corns with chemical agents. These products can burn your skin.
Using a pumice stone every day will help keep calluses under control. It is best to use the pumice stone on wet skin. Put on lotion right after you use the pumice stone.
Ulcers occur most often on the ball of the foot or on the bottom of the big toe. Ulcers on the sides of the foot are usually due to poorly fitting shoes. Remember, even though some ulcers do not hurt, every ulcer should be seen by your health care provider right away. Neglecting ulcers can result in infections, which in turn can lead to loss of a limb.
What your health care provider will do varies with your ulcer. Your health care provider may take x-rays of your foot to make sure the bone is not infected. The health care provider may clean out any dead and infected tissue. You may need to go into the hospital for this. Also, the health care provider may culture the wound to find out what type of infection you have, and which antibiotic will work best.
Keeping off your feet is very important. Walking on an ulcer can make it get larger and force the infection deeper into your foot. Your health care provider may put a special shoe, brace, or cast on your foot to protect it.
If your ulcer is not healing and your circulation is poor, your health care provider may need to refer you to a vascular surgeon. Good diabetes control is important. High blood glucose levels make it hard to fight infection.
After the foot ulcer heals, treat your foot carefully. Scar tissue under the healed wound will break down easily. You may need to wear special shoes after the ulcer is healed to protect this area and to prevent the ulcer from returning.
Poor circulation (blood flow) can make your foot less able to fight infection and to heal. Diabetes causes blood vessels of the foot and leg to narrow and harden. You can control some of the things that cause poor blood flow. Don’t smoke; smoking makes arteries harden faster. Also, follow your health care provider’s advice for keeping your blood pressure and cholesterol under control.
If your feet are cold, you may be tempted to warm them. Unfortunately, if your feet cannot feel heat, it is easy for you to burn them with hot water, hot water bottles, or heating pads. The best way to help cold feet is to wear warm socks.
Some people feel pain in their calves when walking fast, up a hill, or on a hard surface. This condition is called intermittent claudication. Stopping to rest for a few moments should end the pain. If you have these symptoms, you must stop smoking. Work with your health care provider to get started on a walking program. Some people can be helped with medication to improve circulation.
People with diabetes are far more likely to have a foot or leg amputated than other people. The problem? Many people with diabetes have peripheral arterial disease (PAD), which reduces blood flow to the feet. Also, many people with diabetes have nerve disease, which reduces sensation. Together, these problems make it easy to get ulcers and infections that may lead to amputation. Most amputations are preventable with regular care and proper footwear.
For these reasons, take good care of your feet and see your health care provider right away about foot problems. Ask about prescription shoes that are covered by Medicare and other insurance. Always follow your health care provider’s advice when caring for ulcers or other foot problems.
One of the biggest threats to your feet is smoking. Smoking affects small blood vessels. It can cause decreased blood flow to the feet and make wounds heal slowly. A lot of people with diabetes who need amputations are smokers.
A podiatrist is a doctor of podiatric medicine (DPM), also known as a podiatric physician or surgeon. Podiatrists diagnose and treat conditions of the foot, ankle, and related structures of the leg.
What Are the Qualifications of a Podiatrist?
Podiatrists are the most qualified doctors to care for your feet. They complete four years of training in a podiatric medical school and three years of hospital residency training. This training is similar to that of other doctors.
Podiatrists can specialize in many fields, including surgery, sports medicine, wound care, pediatrics (children), and diabetic care.
Are Podiatrists Board Certified?
Podiatrists can earn board certification with advanced training, clinical experience, and by ultimately taking an exam. The American Board of Foot and Ankle Surgery and the American Board of Podiatric Medicine are the certifying boards for the field.
Look for the “DPM”
Feet are complex anatomical structures, all-in-one stabilizers, shock absorbers, and propulsion engines that are instrumental to overall health and well-being. They require expert care. Be sure you’re seeing the most qualified health-care professional to treat your feet by looking for the letters “DPM” after his or her name. The DPM means a physician has completed years of rigorous foot and ankle training in podiatric medical school and hospital-based residency training, making him or her uniquely qualified to care for this part of the body.
Join us this weekend in cheering for all of our patients running in all events for Twin Cities in Motion!! Stop by our booth at the Expo on Friday and Saturday at the St. Paul River Centre
Researchers at Hebrew University have developed a new sock that will alert Diabetic patients with neuropathy (numbness in the feet) when they may develop pressure ulcers. When the feet are numb, the patient may not feel if they are putting too much pressure on a particular part of the foot. A person without neuropathy would just switch the pressure point by shifting weight to a different part of the foot, or to the other foot, or by loosening a lace, etc. But if you can’t feel, you wouldn’t know that one part of the foot is bearing too much prolonged weight and pressure. This prolonged pressure could cause the skin to break open and a wound, or diabetic ulcer, to form. An infected wound could be the incident that starts the progression toward an amputation of a toe, foot or leg. See the article here.
This appeared in our local paper, the Minneapolis Star Tribune today, Why I Love Winter Running. Let us know your thoughts about winter running. What’s the coldest temperature you ever ran outside in?
On Sept. 20, 1862, Abraham Lincoln had a lot on his mind. The Civil War was raging, and just days later he would issue the preliminary draft of the Emancipation Proclamation.
Still, the weary president found time to sit down to write a testimonial to his podiatrist.
“Dr. Zacharie has, with great dexterity, taken some troublesome corns from my toes,” Lincoln wrote. “He is now treating me, and I believe with success, for what plain people call back-ache. We shall see how it will end.”
This letter is part of an exhibit that opened last Friday at the New York Historical Society
Check out this fun video from our friends at WonderfulEngineering.com
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